<header>DNS domains for blacklist lookups</header>

<center><tt>maps_rbl_domains</tt></center>
<hr>

This parameter specifies an optional list of DNS domains that publish the
network addresses of blacklisted hosts.

<p>

By default, RBL blacklist lookups are disabled. See the
<a href=opt_smtpd_client_restrictions><tt>smtpd_client_restrictions</tt></a>
parameter.

<p>

The real-time blackhole list works as follows: reverse the client
network address, and reject service if it is listed below any of
the following domains.

<hr>
